*{
    margin: 0;
    padding: 0;
}
ul, ol{
    list-style: none;
}
a{
    text-decoration: none;
}

.carousel-chart{
    width: 500px;
    height: 500px;
    border: 1px solid red;
    margin: 50px auto;
    position: relative;
}
.carousel-chart ul{
    position: relative;
}
.carousel-chart ul li{
    width: 500px;
    height: 500px;
    position: absolute;
    opacity: 0;
    transition: all 1s;
}
.carousel-chart ul li img{
    width: 100%;
    height: 100%;
}
.carousel-chart ul li.opacity{
    z-index: 1;
    opacity: 1;
}
.carousel-chart .btn{
    position: absolute;
    top: 50%;
    margin-top: -25px;
    width: 100%;
    height: 50px;
    z-index: 2;
}
.carousel-chart .btn span{
    width: 50px;
    height: 50px;
    background-color: black;
    color: #fff;
    font-weight: bold;
    font-size: 20px;
    text-align: center;
    line-height: 50px;
    float: left;
    cursor: pointer;
    opacity: .5;
}
.carousel-chart .btn span:nth-child(2){
    float: right;
}
.carousel-chart ol{
    position: absolute;
    bottom: 30px;
    margin-left: -70px;
    left: 50%;
    z-index: 2;
    width: 140px;
    height: 20px;
}
.carousel-chart ol li{
    float: left;
    width: 18px;
    height: 18px;
    background-color: greenyellow;
    font-size: 12px;
    border-radius: 50%;
    text-align: center;
    line-height: 18px;
    margin: 0 5px;
    cursor: pointer;
}
.carousel-chart ol li.active{
    background-color: hotpink;
}